Problem: Rewrite ${\dfrac{8^{-12}}{8^{-9}}}$ in the form ${8^n}$.
Solution: ${ \dfrac{8^{-12}}{8^{-9}} = 8^{-12-(-9)}} $ ${ \hphantom{\dfrac{8^{-12}}{8^{-9}}} = 8^{-3}} $